Linda Cook of the IBS Discrete Mathematics Group was interviewed on a video posted by the Ministry of Science and ICT, featuring international researchers in Korea.

## James Davies gave a talk on the coloring of the plane so that points odd distance apart get distinct colors at the Discrete Math Seminar

On October 31, 2023, James Davies from the University of Cambridge gave a talk at the Discrete Math Seminar on the coloring of the plane so that two points odd distance apart have distinct colors. The title of his talk was “Odd distances in colourings of the plane“.

## Robert Hickingbotham gave a talk on a partition of a planar graph into connected induced subgraphs of bounded size so that all long paths intersect some part more than once at the Discrete Math Seminar

On October 24, 2023, Robert Hickingbotham from Monash University gave a talk at the Discrete Math Seminar on the existence of a partition of a planar graph into connected induced subgraphs of bounded size so that all long paths intersect some part more than once and its application to k-planar graphs and powers of planar graphs. The title of his talk was “Powers of planar graphs, product structure, and blocking partitions“.

## Congratulations Dong Yeap Kang (강동엽) for receiving the Sangsan Prize for Young Mathematicians (상산젊은수학자상) from the Korean Mathematical Society

Our former member, Dr. Dong Yeap Kang (강동엽), has been selected as one of the three winners of this year receiving the Sangsan Prize for Young Mathematicians (상산젊은수학자상) from the Korean Mathematical Society. This prize is for those with outstanding academic achievements in mathematics who are within 5 years of receiving their Ph.D. degree. Dr. Kang was a research student of the IBS Discrete Mathematics Group and received his Ph.D. in 2020 from KAIST under the supervision of Sang-il Oum. He was a postdoctoral researcher at the University of Birmingham for 3 years and currently, he is a Young Scientist Fellow at the IBS Extremal Combinatorics and Probability Group. The award ceremony will be held on October 27, 2023 at the Seoul National University during the 2023 KMS Annual Meeting. Congratulations!

## The 2023 Vertex-Minor Workshop was held from October 15 to 20 at Jeju

The 2023 Vertex-Minor Workshop was held from October 15, 2023 to October 20, 2023 at SONO Belle Jeju in Korea. This workshop aimed to foster collaborative discussions and explore the various aspects of vertex-minors, including structural theory and their applications. There were 17 participants from Korea, Italy, UK, Australia, Japan, and China and participants had great time to discuss open problems related to the vertex-minors of graphs.

Talks

- October 16:
**Sang-il Oum**,*Survey of vertex-minors* - October 17:
**O-joung Kwon**,*The grid theorem for vertex-minors* - October 17:
**James Davies**,*Vertex-minors and preparing graph states* - October 17:
**Paul Wollan**,*Flat-wall theorem for vertex-minors*

## Participants

- Jungho Ahn (KIAS, Korea)
- Rutger Campbell (IBS Discrete Mathematics Group, Korea)
- Katie Clinch (UNSW Sydney, Australia)
- Linda Cook (IBS Discrete Mathematics Group, Korea)
- James Davies (University of Cambridge, UK)
- J. Pascal Gollin (IBS Discrete Mathematics Group, Korea)
- Meike Hatzel (National Institute of Informatics, Japan)
- Kevin Hendrey (IBS Discrete Mathematics Group, Korea)
- Robert Hickingbotham (Monash University, Australia)
- Tony Huynh (Sapienza Università di Rome, Italy)
- Donggyu Kim (KAIST and IBS Discrete Mathematics Group, Korea)
- Eun Jung Kim (LAMSADE, Paris-Dauphine University, France)
- O-joung Kwon (Hanyang University, Korea)
- Sang-il Oum (IBS Discrete Mathematics Group and KAIST, Korea)
- Sebastian Wiederrecht (IBS Discrete Mathematics Group, Korea)
- Paul Wollan (Sapienza Università di Rome, Italy)
- Chuandong Xu (Xidian University, China and IBS Discrete Mathematics Group, Korea)

## Organizers

- Rutger Campbell (IBS Discrete Mathematics Group, Korea)
- J. Pascal Gollin (IBS Discrete Mathematics Group, Korea)
- Meike Hatzel (National Institute of Informatics, Japan)
- Sang-il Oum (IBS Discrete Mathematics Group and KAIST, Korea)
- Sebastian Wiederrecht (IBS Discrete Mathematics Group, Korea)

## Matija Bucić gave a talk on the edge density of graphs with a proper coloring without a rainbow cycle at the Discrete Math Seminar

On October 17, 2023, Matija Bucić from Princeton University gave a talk at the Discrete Math Seminar on the edge density of graphs with a proper coloring without a rainbow cycle. The title of his talk was “Essentially tight bounds for rainbow cycles in proper edge-colourings“.

## Domagoj Bradač gave a talk on upper bounds for the induced size-Ramsey number at the Discrete Math Seminar

On October 10, 2023, Domagoj Bradač from ETH Zürich gave a talk at the Discrete Math Seminar on upper bounds for the induced size-Ramsey number of cycles. The title of his talk was “Effective bounds for induced size-Ramsey numbers of cycles“.

## Welcome Ruonan Li and Laihao Ding, long-term visitors to the IBS Extremal Combinatorics and Probability Group

The IBS Discrete Mathematics Groupo welcomes Laihao Ding and Rounan Li, two long-term visitors to the IBS Extremal Combinatorics and Probability Group.

Ruonan Li is an associate professor at Northwestern Polytechnical University, China. She arrived at IBS on September 29, 2023 and will stay with us until September 28, 2024.

Laihao Ding is a lecturer at Central China Normal University. He arrived at IBS on October 5, 2023 and will stay with us for 1 year.